Thank you for adding one more answer. I have tried /me/accounts to get pages and apps list. Used /me/permissions and /me/?fields=installed to confirm whether current app is installed by the current user. The return value was 1.However,the app hasn't been installed to the pages or apps of current user. How to check it?
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Jingqiang ZhangSep 26 '11 at 2:23

1

There's no way to check true/false in the API, but each time an app is loaded from a page tab you will receive a callback which includes the page ID so you can track it that way, see this answer here for more info: facebook.stackoverflow.com/questions/7232897/…
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IgySep 26 '11 at 6:18